1. Field of the Invention
The present invention relates to an apparatus for wetting dust, and more particularly to an apparatus for mixing a dust-type product with water in an efficient and economical manner while at the same time conveying the wetted product to facilitate its disposal in an environmentally suitable manner.
2. Description of the Prior Art
The major problem with which this invention is concerned relates to the disposal handling of a dry dust-type product. Certain industries, such as the foundry industry, generate by virtue of their operation, a dry dust-type product. In the foundry, this dust product is commonly termed "fines", and it must be suitably disposed of. Metal castings are usually made by the process of pouring molten metal into a mold formed of sand. This sand generally consists of silica grains held together by some bonding material, usually clay or bentonite. The heat from the poured molten metal causes some of the sand to break apart into particles having a dust-like consistency. This dusty product is usually collected at the foundry in a dust collector and conveyed to a truck for hauling to a dump site. As is readily apparent, traditional bulk handling methods cause the dust to become airborne; this presents potential environmental nuisance problems for property owners adjoining the foundry and the dump site.
One solution to the handling problem is to mix the dust product with water, since most of the dust product has a relatively high clay content. Mixing with water causes the dust to form heavier and denser particles incapable of becoming easily airborne; this transformed product can then be handled in the more traditional manner without difficulty.
One system for mixing water with a dust product includes a large hopper where the dust is collected; the dust is then funneled through a bin having a unique geometric structure which is supposed to automatically feed the dust in a controlled manner to a conveyor system, the conveyor then delivers the product to a mixing location. A description of this bin is set forth in U.S. Pat. No. 3,399,466. Another system simply collects the dust in a large drum and within the drum are rotatable blades. A measured quantity of dust and water is simply introduced into the drum to be mixed. The drum is then emptied and a new batch is mixed. These systems are either too expensive or not sufficiently efficient.
It is also to be noted that in order to facilitate handling of the product after wetting, it is important that the right amounts of water and dust product are mixed. For example, insufficient mixing will still create airborne dust problems; too much water, on the other hand, will cause the product to coagulate or become soupy and thereby potentially overload the capacity of the handling system. In addition, a commercially viable system not be efficient, economical and reliable.